This invention relates to a method and apparatus for supporting line-conditioned data stream (LCDS) data—wherein jobs are identified within the data stream—in a networked, job-oriented printing envirornment—where jobs are identified by a particular submission protocol, and the data is in the format of a Page Description Language (PDL). More particularly, the invention is directed to a job-oriented system that also has the ability to process LCDS data. In addition, the LCDS data is processed in a manner that will exploit advanced job management functions of the system.
While the invention is particularly directed to the art of supporting LCDS data in a job-oriented environment, and will be thus described with specific reference thereto, it will be appreciated that the invention may have usefulness in other fields and applications. For example, the invention may be used in any printing environment where integration of job-oriented data and other types of data, such as jobless data or sequential line data that is similar to LCDS data, is desired.
By way of background, in the traditional transactional model of printing, multiple customer print jobs are concatenated into a stream of data that is sent to a printer for processing. The stream of data is referred to as a Line Conditioned Data Stream (LCDS). Once the client (usually a main frame computer) makes a connection, the printer is dedicated to sequentially processing that client's data. The printer may identify and provide status on the jobs within the stream, but those jobs cannot be manipulated independently. Operations at the printer affect the entire data stream.
More recently, in networked publishing and office environments, a very different model of printing has been used. This model is job-oriented or event driven. In this job-oriented model, jobs of various PDL formats can be received simultaneously via multiple protocols. These jobs are typically spooled on the controller, allowing the printer operator to rearrange print order, modify job attributes, hold and restart a job, etc. In this environment, concurrent processing and/or management of multiple jobs may occur. Additionally, the jobs are organized into one or more queues, which may have preset ‘override’ attributes that will be applied to the jobs.
It would be advantageous to be able to accommodate the transactional model of printing (e.g. LCDS data) in a job oriented or event driven environment. Heretofore, no suitable integration of the two models existed in any one system. In this regard, a problem with integrating job-oriented printing with other printing such as that accomplished using LCDS data is that jobs cannot be identified until the data is decomposed and LCDS data does not provide any indication of the end of a job. This results in limited visibility and control by the user. Moreover, the processing of LCDS data by the printer typically requires a dedicated line.
The present invention contemplates a method and apparatus for supporting line-conditioned data stream (LCDS) data in a job-oriented environment that resolves the above-referenced difficulties and others. The invention allows users to have, within a single print system, the benefits of a job-oriented printing environment while simultaneously accommodating the unique requirements of LCDS.